Forgive me Sock, I know u asked specifically about midi. But since u play guitar too, I wanted to make sure u knew about Nashville tuning... Where u string a normal 6 string guitar with only the high strings from a 12 string pack and then double the regular guitar part. This is what I do since I don't own a 12 string guitar. It sounds just like a 12 string but it allows u to play more complex parts with ease. You could also double the Ample midi guitar part using this technique and I bet it'd sound pretty convincing. Again, not what u asked about but I wanted to make sure u were familiar with it.
Btw, 12 string packs usually aren't much more expensive than 6 string packs. So since I own only one acoustic, I always buy 12 strings packs. And when I need a 12 string part, I string up the high/octave strings for Nashille tuning, record the part, then throw away the high strings and replace them with the remaining normal 6 strings. So there's practically no extra expense. And if u own a second acoustic, u could always leave it strung up for Nashville tuning so it's ready to go. Anyway, Cheers bud 👍